benchtests/bench-memchr.c

   1 /* Measure memchr functions.
   2    Copyright (C) 2013-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef USE_AS_MEMRCHR
  20 # define TEST_MAIN
  21 # define TEST_NAME "memchr"
  22 # include "bench-string.h"
  23
  24 typedef char *(*proto_t) (const char *, int, size_t);
  25 char *simple_memchr (const char *, int, size_t);
  26
  27 IMPL (simple_memchr, 0)
  28 IMPL (memchr, 1)
  29
  30 char *
  31 simple_memchr (const char *s, int c, size_t n)
  32 {
  33   while (n--)
  34     if (*s++ == (char) c)
  35       return (char *) s - 1;
  36   return NULL;
  37 }
  38 #endif
  39
  40 static void
  41 do_one_test (impl_t *impl, const char *s, int c, size_t n, char *exp_res)
  42 {
  43   char *res = CALL (impl, s, c, n);
  44   size_t i, iters = INNER_LOOP_ITERS;
  45   timing_t start, stop, cur;
  46
  47   if (res != exp_res)
  48     {
  49       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  50              res, exp_res);
  51       ret = 1;
  52       return;
  53     }
  54
  55   TIMING_NOW (start);
  56   for (i = 0; i < iters; ++i)
  57     {
  58       CALL (impl, s, c, n);
  59     }
  60   TIMING_NOW (stop);
  61
  62   TIMING_DIFF (cur, start, stop);
  63
  64   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  65 }
  66
  67 static void
  68 do_test (size_t align, size_t pos, size_t len, int seek_char)
  69 {
  70   size_t i;
  71   char *result;
  72
  73   align &= 7;
  74   if (align + len >= page_size)
  75     return;
  76
  77   for (i = 0; i < len; ++i)
  78     {
  79       buf1[align + i] = 1 + 23 * i % 127;
  80       if (buf1[align + i] == seek_char)
  81         buf1[align + i] = seek_char + 1;
  82     }
  83   buf1[align + len] = 0;
  84
  85   if (pos < len)
  86     {
  87       buf1[align + pos] = seek_char;
  88       buf1[align + len] = -seek_char;
  89       result = (char *) (buf1 + align + pos);
  90     }
  91   else
  92     {
  93       result = NULL;
  94       buf1[align + len] = seek_char;
  95     }
  96
  97   printf ("Length %4zd, alignment %2zd:", pos, align);
  98
  99   FOR_EACH_IMPL (impl, 0)
 100     do_one_test (impl, (char *) (buf1 + align), seek_char, len, result);
 101
 102   putchar ('\n');
 103 }
 104
 105 int
 106 test_main (void)
 107 {
 108   size_t i;
 109
 110   test_init ();
 111
 112   printf ("%20s", "");
 113   FOR_EACH_IMPL (impl, 0)
 114     printf ("\t%s", impl->name);
 115   putchar ('\n');
 116
 117   for (i = 1; i < 8; ++i)
 118     {
 119       do_test (0, 16 << i, 2048, 23);
 120       do_test (i, 64, 256, 23);
 121       do_test (0, 16 << i, 2048, 0);
 122       do_test (i, 64, 256, 0);
 123     }
 124   for (i = 1; i < 32; ++i)
 125     {
 126       do_test (0, i, i + 1, 23);
 127       do_test (0, i, i + 1, 0);
 128     }
 129
 130   return ret;
 131 }
 132
 133 #include "../test-skeleton.c"